from machine import Pin
from machine import PWM
import time

half_duty = None
Ang = None
T = None
i = None

# 描述此函式...
def setServoAngle(Ang):
  global half_duty, T, i
  T = (Ang - 90) * 36 + half_duty
  return T


half_duty = 4915
pwm22 = PWM(Pin(22))
pwm22.freq(50)
try:
	pwm22.duty(half_duty)
except:
	pwm22.duty_u16(half_duty)
while True:
  for i in range(181):
    try:
    	pwm22.duty(setServoAngle(i))
    except:
    	pwm22.duty_u16(setServoAngle(i))
    time.sleep_ms(20)
  for i in range(180, -1, -1):
    try:
    	pwm22.duty(setServoAngle(i))
    except:
    	pwm22.duty_u16(setServoAngle(i))
    time.sleep_ms(20)